The present invention relates to a coupler for attaching/detaching or replacing an attachment (e.g., bucket, clamshell bucket, or vibration crusher) secured to the end of an arm of a working machine such as a power shovel.
A working machine (e.g., power shovel) widely used for engineering work must be provided with various attachments (e.g., clamshell bucket or vibration crusher) instead of a bucket depending on the type of work.
In a small-scale construction site, various types of work must be generally performed utilizing a single power shovel. In such construction work, the attachment must be replaced by another attachment each time another type of work is performed.
An attachment coupler has been utilized to easily and quickly perform such a replacement operation.
JP-A-2001-288770 discloses technology in which a coupler includes a movable hook and a stationary hook, and the movable hook is driven and secured using a hydraulic cylinder so that attachment-side connection shafts detachably engage with the hooks. According to this technology, since the coupler must be provided with a hydraulic cylinder reception/operation space, the size of the coupler increases. As a result, the attachment may interfere with a working machine or the like due to an increase in the swing radius of the attachment.